Lint and test on GitHub Actions

[hugovk]

For #1121.

• Add a workflow for linting
  • Only runs on ubuntu-latest with Python 3.8
• Add a workflow for poetry run pytest
  • Runs on ubuntu-18.04, ubuntu-16.04, macos-latest
  • Maybe a single ubuntu-latest would be enough?
  • With Python 3.6-3.8

Examples:

• Lint https://github.com/hugovk/isort/runs/436539359?check_suite_focus=true
• Test https://github.com/hugovk/isort/runs/436539366?check_suite_focus=true

Not included:

• Deploy. This could be done with https://github.com/pypa/gh-action-pypi-publish
• Codecov. Tokenless upload is not yet supported, like with Travis. This either needs the token putting as plaintext in the repo (like Implement code coverage in GitHub actions pytest-dev/pytest#6441), or waiting a bit longer, they're working on it now (Is there a way to make this work with a PR from a fork codecov/codecov-action#29 (comment))
• Windows. Omitted for now, the poetry install was failing. As this issue is about replacing Travis and not AppVeyor, that can wait.

For some reason, 3.8 on macOS is failing:

>           assert str(tmpdir.join("file1.py")) in out
E           AssertionError: assert '/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0/file1.py' in ''
E            +  where '/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0/file1.py' = str(local('/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0/file1.py'))
E            +    where local('/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0/file1.py') = <bound method LocalPath.join of local('/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0')>('file1.py')
E            +      where <bound method LocalPath.join of local('/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0')> = local('/private/var/folders/24/8k48jl6d249_n_qfxwsl6xvm0000gn/T/pytest-of-runner/pytest-0/test_command_line_True_0').join

https://github.com/hugovk/isort/runs/436539509?check_suite_focus=true#step:7:218

Any ideas?

[timothycrosley]

This all looks fantastic! Thank you! Similar to PyLint, I'd feel okay leaking the coverage key if needed for now. I'm not sure the cause of the mac os failure, but I'm going to work on securing a permanent mac testing machine to help diagnose.

Thanks!

~Timothy

[hugovk]

You'll need to fetch the coverage token from https://codecov.io/gh/timothycrosley/isort/settings, but I can help set it up, if you like.

Would you like it included in this PR or a follow up? It might be better in a follow up, because then GHA will have been enabled in this repo -- it needs the config files to be merged before GHA can be used in PRs.

[codecov-io]

Codecov Report

Merging #1122 into develop will increase coverage by 0.09%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           develop    #1122      +/-   ##
===========================================
+ Coverage    95.77%   95.86%   +0.09%     
===========================================
  Files           49       49              
  Lines         3500     3555      +55     
===========================================
+ Hits          3352     3408      +56     
+ Misses         148      147       -1

Impacted Files	Coverage Δ
isort/pylama_isort.py	100% <0%> (ø)	⬆️
isort/sorting.py	100% <0%> (ø)	⬆️
isort/io.py	100% <0%> (ø)	⬆️
isort/output.py	97.97% <0%> (ø)	⬆️
tests/test_io.py	100% <0%> (ø)	⬆️
tests/test_main.py	100% <0%> (ø)	⬆️
tests/test_isort.py	99.67% <0%> (ø)	⬆️
isort/api.py	93.71% <0%> (+0.06%)	⬆️
isort/main.py	84.83% <0%> (+0.21%)	⬆️
isort/settings.py	90% <0%> (+0.43%)	⬆️
... and 2 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 44c4100...1a7a967. Read the comment docs.

[MCOfficer]

why specify bash here?

[hugovk]

There are different defaults for different platforms:

https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions#using-a-specific-shell

[MCOfficer]

True, but this runs on macOS and ubuntu, which both default to bash. (actually they default to sh, but unless you need something bash-specific that should be fine)

[cclauss]

Current releases of macOS default to zsh, not bash so I approve of the explicit is better than implicit approach used here.

[MCOfficer]

it's a nitpick, so i feel fairly indifferent about it.

[hugovk]

Yeah, Windows would be a great addition for the future as AppVeyor is really slow with a single concurrent job:

Not included:
...

• Windows. Omitted for now, the poetry install was failing. As this issue is about replacing Travis and not AppVeyor, that can wait.